Draft-economizer for furnaces.



9 9 mm 7 2 e n u I. d e t n e t a P N 0 T S U H B L am 5 7 2 6 0 N DRAFTECONOMIZER FOR FURNACES.

(Application filed Nov. 28, 1898.)

(No Model.)

A TTOHNE Y.

m: Momus Films 00., mum-Limo.) WASHINGTON, n. c.

UNITED STATES JOHN B. HOUSTON, OF

PATENT OFFICE.

VANCOUVER, CANADA.

DRAFT-ECONOMIZER FOR FURNACES SPECIFICATION formingpart of LettersPatent No. 627,853, dated June 27, 1899.

Application filed November 28, 1898. Serial No. 697,680- (No model.)

To all whom it may concern:

Be itknown that 1, JOHN B. HoUsToN, a subject of the Queen of GreatBritian, residing at Vancouver, in the Province of British Columbia,Canada, have invented. a newand useful Draft-Economizer for Furnaces, ofwhich the following is a specification.

My invention relates to improvements in economizers for heating the airsupply or draft for furnaces.

The objects of my invention are, first,'to utilize the escaping gasesfrom the furnace for heating the air-supply before it comes in contactwith the furnace. This is accomplished by arranging nests of air-tubeshorizontally in the uptake and passing the incoming air-draft throughthe upper nests to a central chamber and back through lower nests ofpipes to the outer jacket, whence it goes directly to the furnace. Theheated gases pass around the tubes composing the suspended nests ofair-pipes, and by this means a maximum heated su rface is presented tothe incoming flow of air; and my second object is to so arrange thenests of air-tubes in the uptake that they may be easily removed andreplaced in case of breakage or in any other event, and at the same timeutilizing all of the heating-surface in the uptake for preparing theincoming air for the furnace to obtain the most economical results. Iattain these objects by the mechanism illustrated in the accompanyingdrawings, in which Figure 1 is a front elevation of an uptake with asection thereof removed, showing the position and arrangement of myinvention. Fig. 2 is a vertical section of the same on the line C C andviewed in the direction of the arrow. Fig. 3 is a detailed plan of oneof the upper nests of tubes sectioned on the line a a, and Fig. 4 is asimilar detailed section of one of the lower nests at the line b b.

Similar letters and numerals designate corresponding parts throughoutthe several views.

The enlarged portion of the uptake A is provided with a jacket 10.Around the top of this jacket 10 and forming a closure between theuptake A and the said jacketis an annularcollarll. Thejacketiscarrieddownward to proximity with the furnace-doors and theair-space connected directly withthe furnace.

As better shown in Fig. 2, the air is introduced into the jacket 10 by aduct 12, and for better and immediate distribution of the air around theuptake a pipe 13 is passed through the same. This not only facilitatesthe flow of air around the uptake, but the pipe 13 is also utilized as aheating-surface to the in comin g air by reason of the said pipe beingdirectly in the flow of heated gas.- Suspended horizontally on eitherside and within the uptake, immediately above the boiler-fines, arenests of air-tubes 14, and placed directly above these tubes are likenests of air-tubes 15. Centrally located between the oppositely-placednests of air-tubes is a vertical air-chamber16. The nests of air-tubeson each side of the u p-' take are secured together by vertical plates17. These plates are perforated, and the tubes snugly fit the aperturesand project slightly beyond the outer surfaces of the plates; but thetubes are so arranged that they may be drawn from the openings in theplates for a reason to appear presently.

At the outer opposite ends of the tubes the upper nests are divided offfrom the lower ones by horizontal plates 18, which form partitions, sothat as the cold air passes downward it will be conducted inward throughthe upper nests of tubes 15 to the inner chamber 16, from where it willreturn back to the jacket 10, and will thus be heated in proportion tothe velocity it is traveling and the condition of the fires in thefurnace.

The central chamber 16 is provided with covers or manholes 19 at the topand bottom.

This allows convenient access to theinner ends of the nests of tubes forrepairing or re moving any of the parts.

When it is desirous to come at the nests of surfaces exposed to the coldair danger of any of the parts being burned or damaged by heat isminimized very much, as the flow of cool air will keep the temperatureof the metals down, and a further advantage is the beneficial andeconomical effect of exposing all of the heated parts inclosed by thejacket to the incoming flow of air, this being one of the essentialfeatures requisite.

It is obvious from the arrangement of the nests of tubes that the draftmay be natural, forced, or induced, as the air will first radiate fromthe pipes 12 and 13 and pass to the opposite outer ends of the pipes 15,through which it will be introduced to the chamber 16 and through thelower pipes 14 to the furnace without fans for forcing or inducing, thisflow being caused by the draft of the furnace.

It is evident that although the air-tubes will give better results bybeing arranged in nests on opposite sides of the uptake, in smallfurnaces it will be more economical in construction to dispense with thecentral chamber 16 and let the tubes extend across the uptake to thejacket on each side, in which case the colder air would pass from theleft or right side of the jacket, as most convenient, and return to thesame side and thence to the furnace. This would be advantageous Wherethe uptake was narrow, the modification being merely to dispense withone upper and lower set of the nests. The air would travel right acrossinstead of to the central chamber only.

Having now described my invention,what I claim as new, and desire to beprotected in by Letters Patent, is

1. In an economizer for furnaces, in combination with an uptake for thegases and smoke, a jacket surrounding said uptake in proximity to thefurnace, means for passing air thereto; of nests of tubes placedhorizontally on opposite sides within the uptake, a

central chamber dividing the said tubes, other nests of tubes arrangedbeneath the first ones, and communicating from the central chamber tothe jacket beneath parting-walls 18,which divide the lower tubes ofi?from the upper ones, as specified.

2. In an economizerforfurnaces, having an uptake to receive the heatedgases generated thereby,the combination of a jacket surrounding thelower part of the uptake, and means for distributing cold air around thesaid uptake within the jacket, of a central chamber 16 arranged in theuptake; of anest of tubes 15 on opposite sides of the central chamber,said tubes communicating between the jacket and the central chamber, andof other nests of tubes 14 arranged beneath the tubes 15, which alsoconnect between the jacket and the central chamber, and parting-plates18, which divide the outer ends of the nests of tubes, as and for thepurposes specified.

3. In combination with an uptake, havinga jacket arranged thereon andmeans for passing a flow of air to the jacket; of a central chamber 16arranged in the uptake, perforations in the opposite walls of thechamber '16, and the outer side walls of the uptake, nests of tubes orpipes passed through said perforations communicating between the jacketand the chamber 16, and horizontal parting-Walls 18 placed between thejacket and the uptake dividing the outer ends of the upper and lowernests of tubes, so that the incoming air-flow will pass through theupper tubes to the central chamber and back through the lower nests oftubes to the jacket, as specified.

JOHN B. HOUSTON.

Witnesses:

ROWLAND BRITTAIN, LoUIs KERSHAW.

